PDA

View Full Version : Did I order the wrong twist?


Samdweezel05
03-25-2011, 06:05 PM
Ordered a 28" .338 Lapua Magnum barrel today and I went with a 1:9 twist. I am wondering now if I should have gone with the 1:10.
Uncle Jack
03-25-2011, 06:11 PM
What weight bullets do you plan to shoot?

uj
Samdweezel05
03-25-2011, 06:16 PM
Probably nothing heavier than a 300gr.
sinman
03-25-2011, 06:35 PM
most are 9.3-10 twist, you might have trouble with the lighter bullets but you should be fine on the 300gr and the solid cnc turned bullets if you are going to shoot them.
Samdweezel05
03-25-2011, 06:42 PM
I think I am going to call Amy back Monday and change it to a 1:10.
helotaxi
03-25-2011, 11:00 PM
Leave it a 1:9. The bullet cannot be too stable but it can be marginally stable or unstable.
sinman
03-26-2011, 09:25 AM
you can have too much rpm from too fast of a twist and tear the jackets off bullets. As for the big 338's I don't know if it is a problem but smaller ones it can be.
helotaxi
03-27-2011, 12:14 AM
you can have too much rpm from too fast of a twist and tear the jackets off bullets. As for the big 338's I don't know if it is a problem but smaller ones it can be.

Definitely not a problem with .338 bullets and only a problem with certain small caliber bullets and 1:7 twist barrels, specifically certain varmint bullets designed for use with 1:12 or 1:14 twist.